Bio Study Guide #2 PDF

1. Name the functions of the integumentary system Protection, Temperature Regulation, Sensation, and Metabolism 2. Know the different layers of the skin, including its major divisions as well as the subdivisions of the epidermis and dermis Epidermis: outermost layer, made of epithelia...

1. Name the functions of the integumentary system Protection, Temperature Regulation, Sensation, and Metabolism 2. Know the different layers of the skin, including its major divisions as well as the subdivisions of the epidermis and dermis Epidermis: outermost layer, made of epithelial cells ○ Stratum Basale (Basal layer) ○ Stratum Spinosum (Prickly Layer) ○ Stratum Granulosum (Granular Layer) ○ Stratum Lucidum (Clear Layer) ○ Stratum Corneum (Horny Layer) Dermis: tough inner layer made of fibrous connective tissue ○ Papillary Layer (20%) ○ Reticular Layer (80%) 3. Describe the function of each of the layers of the skin The Hypodermis: sits below the dermis, anchors skin to underlying structures, and thickens are we gain weight Stratum Basale: primary site for new skin cell production in the epidermis Stratum Spinosum: helps make your skin flexible and strong, keratinocytes Stratum Granulosum: forms a waterproof barrier, prevents fluid loss Stratum Lucidum: Reduces friction between the two layers it’s in-between Stratum Corneum: a barrier that protects the body, the outermost layer Papillary layer: blood vessels provide nutrients and oxygen to the epidermis Reticular Layer: strengthens the skin, provides structure and elasticity 4. List the types of cells found in the epidermis and describe their functions Keratinocytes: produce keratin, which gives the skin protection, forms a tight barrier Melanocytes: produces melanin, which gives skin, eyes, and hair their color Dendritic Cells: ingests foreign substances, activates the immune system Tactile Cells: forms sensory receptors for touch 5. Explain the role the skin plays in maintaining calcium levels in the body The skin provides Vitamin D to the digestive system, this helps the body absorb calcium 6. Describe the structure of a nail Free edge - the part you clip Nail plate - visible Root - embedded in the skin Rests on the nail bed, layers of the epidermis Small white semicircle at the bottom - Lunule Skin folds that surround the nail - nail folds 7. Know the internal structure of a hair  Three layers of keratinized cells: ○ Medulla - central core ○ Cortex - bulky layer that surrounds the Medulla ○ Cuticle - outermost layer, provides strength 8. Describe how the shape of the hair shaft can affect the appearance of the hair Round shaft grows straight hair Curved(bean-shaped) grow wavy hair Oval shape grows curly hair 9. Know the different types of sweat glands and how/when they function Eccrine Glands - traditional sweat glands, over most of the body and open directly onto the skin's surface Apocrine Glands - found in the armpit and genital areas, lie deeper in the dermis, and empty into hair follicles. Begin functioning at puberty and are more viscous 10. Know what sebaceous glands produce and their function Sebaceous Glands: found all over the body, secrete oily substance sebum, softens/lubricates skin 11. Know the different types of skin receptors and what sensations they are specialized to detect Meissner’s corpuscles (in dermal papillae) allow us to sense touch Pacinian corpuscles (in deeper dermis) allow us to sense pressure Hair follicle receptors, free nerve endings throughout the skin 12. Describe the three types of skin cancer and the differences between them Basal Cell Carcinoma - the most common type, occurs on sun-exposed areas of the face Squamous Cell Carcinoma - usually on the head or hands, grows rapidly Melanoma - cancer of the melanocytes, most dangerous, appears often from pre-existing moles 13. List the “ABCDEs” of melanoma A - Asymmetry B - Border C - Color D - Diameter E - Evolving 14. Describe the differences between the three degrees of burns First Degree - Only epidermis damaged, redness and swelling Second Degree - Epidermis and upper layer of dermis damaged, blisters appear Third Degree - Entire thickness of skin, nerves destroyed, skin grafting needed 15. Name the functions of the skeletal system  Gives the body shape and form, supports and protects our tissue and organs 16. Describe the gross anatomy of a bone Compact bone - dense outer layer appears smooth Spongy bone - internal layer, honeycomb of thin, flat, structures Periosteum - covers the outside of the bone Endosteum - Covers the inside of the spongy bone 17. Describe the microscopic anatomy of a bone Cells: Osteogrenic -> Osteoblast -> Osteocyte -> Osteoclast A bone's microscopic anatomy is primarily composed of cylindrical structures called osteons, which consist of concentric rings of calcified matrix (lamellae) surrounding a central canal (Haversian canal) containing blood vessels, with bone cells (osteocytes) trapped within small spaces (lacunae) between the lamellae, connected by tiny channels (canaliculi) that allow for nutrient transport 18. Describe the three ways in which PTH acts to increase calcium levels in the blood Parathyroid Hormone ○ Efflux of calcium from the bone ○ Decreased loss of calcium in urine ○ Enhanced absorption of calcium from the intestine 19. Name the four types of cells found in bone and describe their functions Osteogenic cells – mitotically active stem cells, found in periosteum and endosteum Osteoblasts – bone-forming cells that secrete bone matrix Osteocytes – mature bone cells in the lacunae; sense stress and respond to mechanical stimuli Osteoclasts – Giant multinucleate cells, that break down bone 20. Describe how bones are formed in the embryo Ossification - cartilage is gradually replaced by bone tissue Cells called osteoblasts differentiate from mesenchymal cells and start secreting osteoid, a collagen-rich matrix that will mineralize to form bone 21. Describe how bones grow post-natally Longitudinal growth: Occurs at the epiphyseal plates Appositional growth: Increase in bone thickness 22. Describe how and when bones remodel themselves Continuous process of bone resorption and formation Occurs in response to mechanical stress and calcium levels 23. Know the different regions of the vertebral column and what their functions are Cervical: Supports the head, allows for neck movement - Thoracic: Supports the rib cage, protects thoracic organs - Lumbar: Supports the lower back, bears the weight of the body  - Sacral: Connects the spine to the pelvis - Coccygeal: Vestigial tailbone 24. Distinguish between the structures of the five types of vertebrae Cervical: Small body, bifid spinous process, transverse foramina Thoracic: Larger body, long spinous process, facets for rib articulation Lumbar: Largest body, short and thick spinous process Sacral: Fused vertebrae forming the sacrum Coccygeal: Fused vertebrae forming the coccyx 25. Describe how the intervertebral discs function and their structure Structure: Annulus fibrosus (outer ring), nucleus pulposus (inner gel-like core) Function: Absorb shock, allow for flexibility and movement 26. Name the structures that make up the axial and the appendicular skeleton, and distinguish between their functions Axial: Skull, vertebral column, rib cage; supports and protects organs Appendicular: Limbs, pectoral and pelvic girdles; facilitates movement 27. Know the major structural differences between the pectoral and pelvic girdles Pectoral girdle: More flexible, less stable, consists of clavicles and scapulae Pelvic girdle: More stable, less flexible, consists of hip bones 28. Know the major bones of the axial and appendicular skeleton Axial: Skull, vertebral column, rib cage; supports and protects organs Appendicular: Limbs, pectoral and pelvic girdles; facilitates movement 29. List and describe the major disorders of bone remodeling, and know the differences between them Osteoporosis: Decreased bone density, increased fracture risk Osteomalacia: Softening of bones due to Vitamin D deficiency Paget's disease: Abnormal bone remodeling, enlarged and misshapen bones 30. Describe the steps in bone repair after a fracture Hematoma formation - Fibrocartilaginous callus formation - Bony callus formation - Bone remodeling